The chemical synthesis of 2'(3')-O-aminoacyloligoribonucleotides and 2'(3')-O-(N-acylaminoacyl) oligoribonucleotides with nucleotide sequences identical to or resembling those of the 3' terminus of tRNA will be carried out. These compounds will be used as models of the 3' terminus of AA-tRNA or peptidyl-tRNA in order to study its involvement in the various steps of protein biosynthesis on ribosomes. The various analogs of antibiotics will also be synthesized and investigated in protein biosynthesis systems. The chemically prepared compounds will be tested for antineoplastic activity in tissue culture systems and in vivo. BIBLIOGRAPHIC REFERENCES: D. Ringer, S. Chladek and J. Ofengand. Enzymatic Binding of Aminoacyl Transfer Ribonucleic Acid to Ribosomes: The Study of Binding Sites of 2' and 3' Isomers of Aminoacyl Transfer Ribonucleic Acid. Biochemistry, 15, 2759 (1976). S. Chladek, D. Ringer and E.M. Abraham. Fluorescent 2'(3')-O-Aminoacyl-nucleosides - Acceptor Substrates for Ribosomal Peptidyltransferase. Nucleic Acids Research, 3, 1215 (1976).